Pulmonary arterial hypertension (PAH) is characterized by widespread obstruction and obliteration of the smallest pulmonary arteries. When a sufficient number of vessels are occluded, the resistance to blood flow through the lungs increases, and the right ventricle attempts to compensate by generating higher pressure to maintain pulmonary blood flow.

Myostatin is a protein that regulates both muscle mass and muscle metabolism. The myostatin null mouse has a hypermuscular phenotype owing to both hypertrophy and hyperplasia of the myofibres. Cardiac myostatin acts in an endocrine fashion to communicate to skeletal muscle and induce atrophy.

Here, we aimed to identify key changes in the muscle phenotype, explore the expression, actions, specific signalling pathways and regulation of myostatin in smooth muscle (vessels).